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My spouse and the the so-called “Wife Acceptance Factor” (WAF) were the motivation behind me creating this website.  For as long as we have been enjoying our home theater system, there has been a problem with understanding the dialog coming from the center channel. I have now discovered a simple and inexpensive solution to the problem.  More about this and other natural sound products (that are also WAF compliant) will be explored on this site.

After visiting numerous hi-fi and HT blogs I rarely encountered the term “discreet” applied to audio or loudspeakers.   So, this site was created to allow an interchange of ideas plus a review of the technology and products that truly qualify as discreet loudspeakers.

Although small, unobtrusive speakers are sometimes labeled “discreet” or “lifestyle”, they are generally no more than computer speakers or, cheap little surround “cube” speakers. So-called (and often self-anointed) audio experts are notorious for dismissing this classification of audio gear; dubbing them unworthy of their consideration as serious audiophile grade products.  Their mindset dictates that no little speakers can measure up to the huge tower or panel speakers that they embrace.  Even “bookshelf” is a lowly type of speaker classification that quickly gets their noses up into the air.

But here, possibly for the first time ever, it will be revealed that a clear, natural sounding loudspeaker that meets and exceeds all WAF compliance parameters does exist and is now available at reasonable costs.  Is this not the ultimate goal that we all seek in a true hi-fidelity sound system for the consumer at reasonable prices - meaning a few hundred rather than several thousand dollars?  Is achieving that combination an improbability with existing loudspeaker technology?  Read on!  THERE IS SOMETHING NEW AND PROVEN that breaks through that wall of denial and improbability.

To lay the groundwork, it is given that many high-end loudspeaker manufacturers claim that their product reveals that the natural sound goal has already been achieved. But even with elaborate technical specifications and graphs offered up as proof, more often than not their claims are proven false with revealing listening tests.  Why?  Because it has been discovered that natural sound is rarely ever reproduced (even in expensive high-end speakers) without…

  • compromising or limiting the options of speaker placement,
  • restrictions on speaker alignment toward the listener,
  • limitation of ideal listening location to a single “sweet spot” (narrow dispersion) ,
  • tracing the source of sounds produced by a subwoofer to a box rather than integrating low frequencies with the other speakers in the system for accurate imaging

I encourage you to visit with us often and, please, share your thoughts at the end of each post with your comments.  If you would like to experience and enjoy the wonderful sound of our products first hand, you can order them with a 60-day unconditional money-back guarantee here.

Product store

Discreet subwoofer?

Where's the subwoofer

Where's the subwoofer?

The TBI Magellan sub is hidden behind a antique clock with no compromise of its performance

Behind the clock!

Heard outside the box

(The best sound heard from a subwoofer is no sound at all)

First and foremost is the need for a subwoofer to provide adequate deep bass augmentation (enhancement) to any speakers from mini-monitors to full range, high-end tower systems. This goes for home theater as well as music – two-channel stereo or 5.1 surround sound. Unquestionably, the small fries need a lot of help at the bottom end but so do most of the big boys.

In terms of performance criteria, there is far more at stake in any loudspeaker system than sound pressure level, frequency response and low distortion.

Some audiophiles have given up on hearing the full audio spectrum that really low bass contributes to music because a discrete subwoofer can be obnoxious if it is not discreet. Double talk?  Not really.

A discreet subwoofer can be a critical component in high definition, natural sound reproduction; but only when it integrates with the other speakers does it help achieve the realism of live audio.

We want clean, deep, tight bass but not unless it is blending with the entire speaker system without calling attention to itself.  HDTV lets you see the image through a window as opposed to on the screen.  So, why shouldn’t hi-definition audio demand that you hear the music, not the speaker?

Put another way, it’s what a subwoofer doesn’t do rather than what it does do that matters most.  More double talk? Nope. Setting aside technical design parameters, in an ideal world of speaker performance there should be no sound whatsoever heard from a subwoofer itself.   The box should be completely transparent to the sound – the anti-subwoofer factor.

Why this phenomenon is never mentioned nor described by professional speaker reviewers and acoustical engineers is an enigma. Is it because it really doesn’t exist?  No, it is real alright, and it matters; you just have to experience it firsthand to believe it.

It goes to how well the sub “voices” or integrates outside the box with the other speakers.  This includes the front two main speakers in a stereo system and, additionally, the center channel and rear channels in a home theater surround sound system. Not to be confused with “blending”, integration has to do with hearing the bass imaged in the correct speaker and emanating only from the correct channel where it was recorded.

For music, if a bass guitar was on the left side of the soundstage then that is precisely where should be heard – in the left speaker.  If a kick drum was located in center stage, then it will be heard there even in a two-channel stereo system’s phantom image.  And, when a pipe organ hits that glorious low C it is voiced in all your speakers. With home theater, if there’s thunder or an explosion in a rear channel, it should sound like the sub is voicing with that surround speaker.  This phenomenon has never been heard (or heard of) by most folks.

You can place your head next to a mini monitor or any speaker that is incapable of deep bass and if it is voicing with the subwoofer as described, you will only hear the sub’s bass coming from that speaker!  Once the anti-subwoofer factor is auditioned, it is unbelievable that a speaker that small is really capable of reproducing bass that low… and it’s really not!  The sub is just integrating with the little fellow. Conversely, if you stick your head close to an anti-subwoofer you will hear nothing. How discreet is that?

The anti-subwoofer factor enhances and reinforces the sound stage making it as close to live and natural that any speaker can reproduce. Total sound immersion experienced with a discreet subwoofer – the anti-subwoofer factor – is what I am talking about. Could this be the “Holy Grail” of high definition sound that we all seek at the bottom end?

Magellan subwoofer professional reviews:

Paul Folbrecht: “IMO they are a screaming deal. I’d take the pair at $2500 over any sub I’ve heard, including a $12,500 Wilson Benesch model.”

Dan Dzuban: “The Race for Bass 2: Will You Know the Finish Line When You Cross It?”

Order here

Long, long ago, in a place far, far away, children were once taught to be “seen but not heard” in public places or during family gatherings. Likewise, the WAF (Wife Acceptance Factor) dictates that loudspeakers are to be “heard but not seen” in the home.  Despite the money spent for large tower or furniture-grade speakers, there still might be another price to pay.  Unless there is a separate media room available for these lovely works of art, then the WAF probably kicks in.  If the spouse or significant other views them as loud monstrosities that will not be brought into the home, what are your options?

It is almost universally agreed that small mini-monitor bookshelf loudspeakers (sometimes derisively referred to as “cube” speakers) are not up to the hi-fidelity standards for either audiophiles or serious home theater enthusiasts. Is such a diminutive little prodigy now available that can finally stand toe-to-toe with the big boys?  Could it give a sterling audio performance at an economical price?  Surely that would be a paradigm shift in itself; but how about some totally unique, bonus features such as:

  • Front channels can be hidden behind the TV
  • Surrounds can be hidden behind pictures on a shelf or on the floor beneath furniture
  • Aiming is not critical – point up, sideways or backwards
  • Sweet spot expands to every listening position
  • Play at low volume and still hear crystal clear, full spectrum of frequencies

Does conventional speaker designs make this a “mission impossible” or has some new technology been discovered that the prestigious audio community has grossly overlooked …or ignored?

Product page:

Is the dialog muddy and sometimes unintelligible coming from the center channel in your home theater system? Does your spouse or significant other say, “Turn it up” or, “What did he say?”

Several audio discussion forums have addressed questions like,

  • “I hated how I had to crank up my speakers to be able to hear dialogue in one scene and then have to turn them down in an action packed scene so they wouldn’t be blown out.”
  • “Dialogue on movies is unintelligible and you cannot hear a thing people are saying. I have to put English language dialogue on the screen in order to follow the movie when I can’t completely crank the stereo.”
  • “The sound is a bit ‘muddy’. Dialog doesn’t seem as clear as it could be, and I sometimes feel like I’m missing part of what is being said. I even had my hearing checked to see if I had a problem. I didn’t, thank goodness…”
  • “I can’t hear speech that well. No matter if it is Dolby Digital, DTS, or whatever. The speech gets washed out by the surround sounds (not necessarily the surround speakers themselves). I thought all I needed to do was to increase the volume of the center speaker and that would take care of it. NOPE! It didn’t. I even checked and calibrated all surround speakers to be exact with a sound level meter and pumped the center channel even louder. No good. I checked my connections on the back of the receiver to make sure each speaker was hooked up correctly and all is correct. When I get close to the center speaker, it sounds like it is also letting sounds other than voice/speech come through. I thought the center was supposed to only have speech coming through it. What can I do to remedy this problem? Many thanks in advance!’
  • (My center channel speaker): “It’s not good enough to really be happy with it, but not bad enough to replace it. I’ll wait for some divine intervention.” Read on… it is here already!

Suggestions for solving the problem are all over the map:

  • Purchase a better center channel speaker (how much better will solve the problem?)
  • Purchase a better receiver (same as above)
  • Check the front speakers’ polarity (that is not the problem)
  • Try room treatments (they’re expensive, fail the WAF test and won’t solve the problem)
  • Increase the volume in the center speaker (that’s neither the problem nor the solution; it also fails the WAF test)
  • Engage the “Midnight Mode” if you have a modern receiver with that feature (that monkeys with the dynamic range and compromises the overall sound)

Now some deny the muddy dialog problem exists in their high end systems; well, if you can spend thousands of dollars on speakers, then maybe not.  But even Dolby admits the problem exists and has introduced a so-called “midnight mode” to overcome the problem.  The following was lifted right off of their website:

Midnight mode allows low-volume listening with high-volume benefits, reducing the volume on just the loud effects of a program, increasing the volume on quiet sounds, and maintaining dialogue at a consistent level. A Dolby Digital feature applies dynamic range compression that preserves low-level sounds, prevents dramatic passages from getting too loud, and keeps dialogue intelligible during lower-level listening.

The amount of compression is not arbitrary, but is decided in advance by the soundtrack’s producers and coded right onto the soundtrack.

Some Dolby Digital decoders let you select various amounts of the available compression (for example, 50, 75, 100 percent), while others provide only 100 percent when the compression mode is selected.”

But this begs the question: if there is an acoustic problem with one’s center channel loudspeaker’s dialog clarity, should we try to overcome that with further manipulation of the signal with compression and equalization algorithms that effect the overall sound?  Or, put another way, why can’t you hear everything at the volume you like - low or high?

What if you could add a simple dialog augmentation (corrective/clarifying/enhancement) device that…

  • could be wired in parallel with the existing center channel speaker
  • was a passive module that required no additional power supply or amp
  • is “discreet” – passes the WAF test
  • creates crystal clear dialog using any receiver or speaker
  • smooths out speaker response of all front channels
  • is so inexpensive that it would fit anybody’s budget

Does this sound like another “Mission Impossible” task for audio engineers?

How to order

No speakers visible from the TV viewing side

No speakers visible from the TV viewing side

This is the ultimate WAF setup - no front speakers visible

This is the ultimate WAF setup for HT

Not to be confused with “discrete” which means separate or distinct, some loudspeakers are described as “discreet” simply because they are small, unobtrusive, or look like artwork. However, in terms of loudspeaker design and performance, “discreet” has a broader definition. More accurately, “discreet” must define both its subtle appearance plus the audio disappearing act it performs in the listening environment.

The WAF rule requires that a speaker never draw attention to itself visually and not have to be played loud for enjoyment. Hi-fidelity standards require that a speaker never draw attention to itself aurally; i.e., the sound stage should be natural, realistic and not sound like it is coming at you from inside a box. Don’t just think, listen… outside the box.

To Order:

Driver component w/crossover

Driver component w/crossover

When you see the DAD-1 driver, it looks like a tweeter …and it really is. But beyond its appearance it does much, much more than any other tweeter design out there.

Originally, the HDSS® (High Definition Sound Standard) model TWEP51 was and still is offered as a pair of these tweeters for use in automotive applications.  Then it was discovered that one of these drivers added to the center channel in home theater sound systems would miraculously clear up unintelligible dialog; so an introduction to that market was initiated through this website.

Using patented ETL™ (Embedded Transmission Line) technology, the DAD-1 driver is critically damped for its full bandwidth and void of diaphragm breakup. This normalizes acoustic impedance and maintains proper dispersion for the bandwidth of the driver. No metal or unnatural material is used for diaphragm breakup control with a dome employing silk material for its natural damping qualities.

Without getting into cross-over networks and the way a conventional tweeter performs in a given 2-way loudspeaker system, the DAD significantly augments overall sound clarity for virtually anyone who, through aging, suffers a natural loss of hearing acuity, especially in the higher frequency range.   The five significant things that enhance the overall performance of the interfaced loudspeaker with which it is used are:

1) Increases clarity in the 3.5 – 4 kHz range where human hearing has its greatest sensitivity

2) Forces the integrated speaker to be sympathetic at this range and smooths out its frequency response throughout its entire range

3) Enhances the dispersion characteristics of the speaker - facilitates off-axis imaging (allows “sweet spot” listening anywhere in the room)

4) Enhances and clarifies sound stage imaging

5) Provides the fast impulse response for lower frequencies to provide the proper character for bass sounds.

Want one?

“The improper use of physical laws has stagnated the development of accurate loudspeakers throughout the 20th century.”

CORRECT PISTON THEORY FOR LOUDSPEAKER OPERATION

The purpose of any piston – gas-cylinder system is to produce the desired work. The system can function using a group of pistons to operate a crankshaft or a single piston can do all of the work. The system must be sealed to be effective in enclosing the gas. Virtually all pistons operate to change the volume of a gas to produce work or the gas heats and the piston changes position. The study of thermodynamic systems that involve pistons typically focuses on the work done and the temperature-pressure change involved in accomplishing this. The focus of the physical study can be on the macroscopic level whereas the terms of concern are pressure (P), Temperature (T) moles (n) and volume (V). These terms describe an ideal gas without concerns for microscopic properties, which exist for real gases and are important to the thermodynamic system. When observing thermodynamic behavior at this level the primary component to cause heat is the volume allowed for the molecules contained within the cylinder. Macroscopic studies
associate the speed of the internal molecules with a heat increase or decrease. Forcing a specific number of molecules together in a small volume will increase their speed and collision rate therefore the heat and the pressure associated with the walls and against the movable piston will also be greater. If the walls were flexible there would be a bulge in them when the piston is pushed down. When the piston retracts, the space allowed for the molecules will be greater to cause the temperature to lower and the momentum of the molecules to slow. This will reduce the pressure on the walls of the cylinder and the negative pressure on the piston.

Macroscopic observations involving an ideal gas demonstrate a pressure increase due to a volume decrease with a transition from low to high pressure governed by the single mode of molecular translation motion. The use of a real gas in the cylinder introduces the microscopic properties of the gas molecules and their real world properties that cannot be ignored. Microscopic properties involve the atomic elements of the molecules and the attractive and repulsive forces observed when placing these elements in close proximity to each other. The additional terms involved are the molecular mass, velocities, momenta and
kinetic energies. While real gases may behave as ideal under moderate pressures where the molecular state is of mild attraction, their behavior changes when confined, to a greater attraction and then repulsion. The electrons of a real gas will attract nuclei of others and vice versa causing the atoms to be closely spaced however any further reduction of volume by the piston will cause violent repulsion as the electrons and nuclei of the atoms are spaced too close to each other. This is the real world operating environment for the enclosed loudspeaker and results in violent resonant behavior for the diaphragm. Longer wavelengths and higher levels are elements of the composite wave that are compressive relative to small signal levels. With the loudspeaker diaphragm the lower frequencies are affected first as they create greater motion that results in compression and resonance. The stiffness of the diaphragm is enhanced by the macroscopic and microscopic properties of air causing resistance to the motion of its mass and therefore resonance. Typically this resonance sets in at a lower frequency when the driver is not mounted and the driver mechanical compliance establishes the stiffness. The un-mounted driver will not produce work at low frequencies as the acoustic outputs cancel around the diaphragm.

EFFECTS OF MICROSCOPIC PROPERTIES OF REAL GASES

effects-of-microscopic-properties-of-real-gases

Widely separated gas molecules attract each other and maintain equilibrium between attractive and repulsive. This attraction becomes greater as the spacing is reduced but turns to a strong repulsion when the molecules get too close together. There is a certain degree of separation prior to repulsion that must be maintained for the constant pressure operation to occur. When the molecules are nearing the critically defined repulsive distance their nuclei and electrons react causing an exponential increase in heat. It is this reaction, which enhances the piston resonance and pushes it to a higher frequency. The Embedded Transmission Line must maintain the pressure within an arbitrary +/-1 range for molecular spacing for attraction and repulsion. It does this using captive molecular vorticity that dissipates heat within its structure thereby cooling the cylinder volume. The goal is to maintain the temperature of the gas behind the piston so that the molecules are spaced within the narrow range exhibiting mild attractive-repulsive forces. It is in this range where a real gas exhibits the macroscopic properties of an ideal gas with pressure changes relating primarily to kinetic motion of the molecules that allow work to be done. The molecular cooling within the ETL™ advances toward the cylinder volume to regulate molecular spacing within the cylinder. This thermal process is to maintain a laminar (linear) stream when the piston moves towards the gas creating pressure that is essentially constant throughout the -work cycle as the volume is reduced. The positive going cycle reverses the piston separating and cooling the gas molecules to maintain pressure constant as the piston increases cylinder volume. The pressure is maintained as the molecules remain within the +/-1 range for molecular spacing. The current theory of operation for loudspeakers (including closed tweeter or midrange designs) involves both macroscopic and microscopic thermal modes to cause a heat increase. The microscopic mode is highly reactive but both modes contribute to molecular heating and exponentially increasing pressure preventing the diaphragm from accurately performing the work that it is intended to do. It is apparent that from the initial days of loudspeaker development the primary goal was to prevent cancellation of front and rear waves of the driver. The macroscopic aspects of pressure were observable and no importance or observations of the microscopic properties were possible in the early days. The pressure problems, although currently obvious, have not been addressed to date with the exception of the ETL™ developed by TBI Audio Systems to allow for the consideration of the extremely important atomic properties of a real gas, air. The wide dynamic range of the ear makes it responsive to this unnatural phenomenon making it the number one obstacle to natural sound reproduction. The improper use of physical laws has stagnated the development of accurate loudspeakers throughout the 20th century.

- Jan Plummer

A great review of the mini monitors and class D amplifier was done by MaximumPC. This is the same system that we are packaging for the visually and hearing impaired in the iBAG portable sound system. Michael Brown also reviewed three other competing products where he used the TBI system as a reference:

The latest review of the Magellan™ passive subwoofers powered by the new TBI Magellan MGD-200 subwoofer amplifier can be found at www.audaud.com/article.php?ArticleID=7336

In the review, Clay Swartz states unequivocally, “The TBI subwoofers are the only subwoofers I would use in a music system.” There is also a link to his original review of the Magellan subs done almost 6 years ago at VIII SU Subwoofer + power amp. This is especially worth reading because it delves into the role of a subwoofer in a music system and how it interacts with the room acoustics.

iBAG™ Review

I didn’t have any problems hooking up the speakers. After hooking up the speakers I connected them to my mp3 player. I listened to them at low and high volume and found the sound to be very clear and balanced at both levels. I tried turning them away from me and still could hear the sound clearly without any noticeable difference. They seemed to have even frequency response across the entire spectrum, although I had no way of accurately measuring this.  They didn’t have the accentuated harsh high end you hear in many other speakers, particularly when listening to digital audio.  The fact that they can be used with the included amp as well as being hooked up to a larger stereo system makes them  a good value. I think they make a very nice listening package.

Tim Cumings

iBAG™ system

Introducing the BioLinks® Audio Freedom™ System

We are pleased to have Brian Oglesbee (a/k/a “Sightless Wonder”) join our team in the capacity of Director of Marketing for the Visually Impaired.  Brian is a member of the National Federation of the Blind (NFB) and a high school social studies teacher in Thomaston, GA.  Although he is totally blind, Brian hosts weekly music trivia shows at a local tavern using a portable DJ system with his BioLinks® Audio Freedom™ System. Brian has been an avid spokesman for the blind about the amazingly transparent, clear and natural sound that his system produces and how much it means to him.

Brian has dubbed this package the iBAG™ system (BioLinks Audio Gear). Here are a few reasons why he endorses our system as the ideal portable Hi-Fidelity sound enhancement system for anyone, especially the blind:

  1. Distortion-free sound – Comparable to tower loudspeakers that cost thousands of dollars, these little Majestic Diamond™ “cube” speakers are distortion free yet very inexpensive.  Such clear and natural sound is only attainable from such a small speaker package because of the innovative ETL (Embedded Transmission Line) technology invented and patented by Mr. Jan Plummer, president of TBI Sound, Ltd.
  2. Lifestyle Audio with the “Freedom” of Mobility – The BioLinks® Audio Freedom™ portable sound system consists of two TBI Majestic Diamond™ MD-1 speakers and a small Dayton DTA-1 portable, digital “T” amplifier. This “mobility” system can go anywhere.  If used with a laptop or cell phone, the system can be moved around the house, carried to a tailgate party, a picnic or the beach. You can hear clear, natural audio from the music, sound reader or audio books stored on your cell phone, iPod®, CD player or laptop computer.
  3. Transparent Sweet Spots – These diminutive speakers do not have to be aimed at the listener due to their transparency and wide dispersion characteristics. The Majestic Diamonds can be placed on a desk; a bookshelf; behind furniture on the floor; pointed forward; aimed sideways or backwards.  In fact, they can be hidden virtually anywhere and still sound the same - wonderful!  Most other loudspeakers have a restricted listening area or “sweet spot” that requires you to sit in one particular place to enjoy the best sound.  Isn’t it somewhat unsociable when everyone in the room cannot equally enjoy the sound regardless of where they sit or stand?  Transparent and natural sound is very difficult to achieve in any loudspeaker. Transparency means that the sound stage is always imaged properly and never perceived as coming from a loudspeaker box.
  4. Unsociable Sound – Have you ever been at a party or in a nightclub where the music is being played so loudly that you cannot carry on an intelligible conversation without shouting?  Blind folks are especially annoyed by this.  But now the BioLinks® Audio Freedom system finally offers a solution.
    1. Play it at lower levels and enjoy the full dynamics of the music… there is no fall-through of the full spectrum of low to high frequencies as the volume is turned down.
    2. Play it at live concert sound levels and you can still understand conversations clearly and at normal speaking levels. Telephone calls are easily heard without the typical invasion of your background music into the conversation.
    3. No worries about your sound penetrating through walls or ceilings, even if you live in an apartment or condo. That means your neighbors will not be assaulted by intrusive noise even if you want to turn it up loud!

Brian feels that the iBAG system will open a new world for the visually impaired essentially because they are far more sensitive to and dependent upon sounds in their everyday lifestyle.  Accuracy and transparency in reproducing natural sound will give the blind expanded communicative capabilities and an enhanced quality of life.

The BioLinks® Audio Freedom system comes complete with the class D amplifier and a pair of Majestic Diamond™ speakers, all interconnect cables plus a tote bag (hence the iBAG™ moniker). Simple hook up instructions are included and are easy to follow, even for the blind.  Special, deep discounts on this packaged system will be available for members of organizations for the blind. If you are a member of the NFB, ACB, or AFB, please email us for the special price on this system as well as other ETL/HDSS products.

Speaker Quality and Psychological Stress Test Report

Test Master: Alan Chou, Licensed Psychologist
Experience: Licensed Psychologist (Taiwan and China)
Master Degree in Psychology, University of Pittsburgh
Director, United Counseling Center
TV Program host, (CTITV, Taiwan) & (Young Channel, Shanghai)
Test Date: July~August, 2007
Test Venue: United Counseling Center
10F, No. 41, Sec. 1, ZhongXiao E. Rd, Taipei City,
Taiwan R.O.C.

1. Summary:

Ten volunteers (5 male, 5 female, please refer Note 1) participated in the test, which required listening to different music played from four speaker systems. Two of the speaker systems were modified with the ETL-Module and the other two were not modified. The participants were subjected to the Heart Rate Variability (HRV) test which measures psychological stress.

The results indicate that the two types of speaker systems (speaker systems and earphones) containing the ETL-Module (as modified by Formosa Prosonic) significantly lessened the psychological stress levels of the participants.

(See Note 2)
The ETL modified earphones dramatically reduced the stress levels of the participants by 14.32%. The ETL modified speaker systems reflected a significant stress reduction of 7.33%.

The sound testing involved the playing of four different styles of music (please see Note 3). However the musical style had no effect on the resulting measurements.
2. Test Environment

Environment description of the Test Lab :
I. The test was conducted in an isolated room (Length 4.50m / Width 3.80m / Height 2.25m)
ii. The distance between the speakers and the volunteers was 3.90m.
iii. The music was played at a normal volume
3. Conclusion:
1. The speaker systems and earphones that contained the ETL-Module significantly reduced the psychological stress levels of the participants in the study.
2. Statistically, any stress reduction level that exceeds 5% is a noticeable and meaningful test result.
3. The stress reduction by ETL modified earphones and speaker systems of 14.32% and 7.33% respectively, demonstrate a clear and resounding superiority for reducing listeners’ psychological stress when this technology is applied to loudspeakers or small speaker (ear-phone )

etl-stress-test-image-1

etl-stress-test-image-2

stress-test-image-3stress-test-image-4

____________________________________________

etl-stress-test_00051

stress-graphs21Note 3:
Music used:
Track 3, Classic: Dvorak “From the new world” No. 9 in E minor OP95
Track 12, Female vocal: Mariah Carey “So Blessed”
Track 14, Female vocal: Gloria Estefan “Oye”
Track 24: Assorted sound for movie
(1) ETL module Speaker System 3inch driver (2) ETL module-Earphone
speaker size: 3 inches
Test Master:  Alan Chou, Licensed Psychologist

ETL for dummies

etl-for-dummies21
etl-for-dummies3

HDSS® - THE HIGH DEFINITION SOUND STANDARD

HDTV is possible because of the special displays or video monitors recently developed that allow the high resolution electronic digital video signals to be displayed as intended. The high definition viewing experience is flawed without the accompanying sound having a similar degree of resolution. There are no objectively comparable sound monitoring devices for High Definition Audio (HDA).

Audiophiles and the supporting high-end industry have typically sought solutions for the monitoring of high resolution audio however their efforts produce results which are highly subjective, difficult to replicate and have no consideration for cost or size. The HDSS® standard must accomplish what the high-end industry is attempting to achieve but for the mass market application in simple objective monitors which replicate HDA on a sonic level. In essence, the sound must be reproduced objectively as the picture for all situations. In the simplest applications the human voice should be naturally intelligible. The official name for HDSS® certified speakers is that of HDSS® Audio Monitor. Size is a consideration for effective general application of HDSS® audio monitors when they must be externally added to an existing product. Small size also considers all of the necessary elements for full HDSS® certification. Larger HDSS® qualified products will typically deviate from the standard by nature of design. Embedded speaker products can qualify for HDSS® certification but typically not 100% as they are fixed in position.

DIGITAL AUDIO MEDIA:

HDA is available for transmission, recording and playback but at the point of audible playback the high resolution of the electronic signals is obscured by loudspeaker distortions. The preservation of the original audio signal is enhanced due to high sampling rate digital technology while no attempt is made to improve loudspeaker resolution. Currently extremely high resolution digital files such as SACD and DVD audio have no monitoring standard to assure that their detail will be heard. All digital audio files, even lossy, are enhanced with higher resolution at the loudspeaker. At present HDA is only resolved objectively using high quality headphones which is not the goal of sound content producers.

DIGITAL TELEVISION AUDIO:

HDA/HDTV must be monitored using high resolution audio monitors. The digital audio portion of the HDTV signal must use a suitable audio transducer that allows for presentation of detail. This objective must be met for normal acoustic conditions without regard to placement as will be the situation with the video monitor. The visual objective for panel TV is to show no external speakers while maintaining High Definition Sound apparently originating from the screen itself. The audio for HDTV must be observable at the close distances available for viewing the screen itself or other positions within the viewing area while maintaining intelligibility and a natural character. Headphones are rarely used to monitor television audio resulting in no currently available standard for HDA/HDTV sound monitoring devices.

HDSS® TECHNICAL REQUIREMENTS:

1. SINGLE DRIVER - The audio signal for each channel can only be reproduced by one transducer. The audio signal immediately loses its resolution when it is split and reproduced from more than one driver in the frequency range above 100 Hz. A single driver also allows for the micro dimensions required for multi-applications of the HDSS® Audio Monitor.

The ear cannot interpret the detail due to the many negative issues resulting from signal splitting:

  • The ear loses resolve when the source signal is reproduced at more than one physical location (woofer-midrange-tweeter) to include coaxial arrangements.
  • The ear loses resolve when the signal is produced by drivers of different physical characteristics. Cone (diameter – material – angle), magnetic strength, voice coil characteristics and suspension related differences all cause resolution loss.
  • The ear loses resolve when the signal is split electrically or electronically. The ability of a crossover network to be phase perfect assuming identical transducer characteristics is not feasible. The high costs of crossover networks attributed to high end speaker designs illustrates the diminishing value and impractical use of this approach. Simple systems cannot be developed under these conditions.
  • The ear loses resolve because distance is required for multiple driver integration.
  • The ear loses resolve when signal splitting speaker systems are used for multi-channel operation due to the exponential increase of phase related errors.

2. PISTONIC OPERATION - The single transducer representing the sound monitor for the HDA signals must operate as a piston over the entire audio range to include frequencies from 80 Hz to 20 kHz with little phase error. The angular response must be reasonably flat to 10 kHz and to at least 45 degrees off axis at vertical and horizontal angles. The ability to respond to low frequencies below 80 Hz is essential for operation without a subwoofer even though the output will be with gradual loss. The subwoofer must be an option for HDSS® qualified audio monitors.

The ear cannot interpret detail due to many negative issues related to non-pistonic operation of the single speaker driver.

  • The ear loses resolve when cone breakup is present at the transducer.
  • The ear loses resolve when the acoustic impedance is not maintained constant for all frequencies.
  • The ear loses resolve when the phase is intentionally shifted to extend high frequency response. This can be mechanically as with the transducer design or electrically using frequency boost or cut controls.
  • The ear loses resolve when the angular dispersion is not constant with frequency.
  • The ear loses resolve when the reflections from the room surfaces cause a dynamic change in the nominal acoustic radiation impedance.
  • The ear loses resolve when the acoustic energy output is non-linear with level.
  • The ear loses resolve when the lower bass frequencies are not represented audibly. Rapid loss of bass response is interpreted as unnatural by the ear.
  • The ear loses resolve when the amplifier powering the monitors cannot perform as designed due to loudspeaker induced electrical anomalies present at its output.

3. NON RESONANT BASS EXTENSION - The support of extended lower frequencies can only be accomplished using non-resonant devices. HDSS® low frequency extension cannot be accomplished without adequate control of the resonant characteristics of the driver(s) involved. Poor bass extension should be avoided to maintain required detail. The ear cannot interpret detail due to many negative issues related to poorly resolved lower bass frequencies.

  • The ear loses resolve when the resonant character of the main driver dominates the character of the input signal.
  • The ear loses resolve when more than one resonant frequency is involved in reproducing the low frequencies. Typically this condition refers to a signal of the same origin being reproduced by more than one driver in different alignments.
  • The ear loses resolve when the bass extension technique involves the use of the drivers resonance energy regardless of methods used to damp the output.
  • The ear loses resolve if the bass extension device is crossed over when its group delay is not at or near zero. This is a period when its time response is shifting.
  • The ear loses resolve when the bass extension device is separated by great physical difference from the main audio monitor(s).
  • The ear loses resolve when the room reflections dynamically alter the acoustic radiation resistance of the extension device. This characteristic of immunity to reflections is even more important for lower frequencies and objective performance of the full audio range.

The first two requirements listed above must be met with a minimum of negative issues for HDSS® certification. Sound is analogous so maximum detail is resolved when all three conditions above are met. Each negative issue carries weight relative to its degree of influence. A fully resolved HDSS® system will have a degree of resolution unparalleled by no other system and with a score of 100%. Each negative issue described above will lower that score. To qualify as an entry level HDSS® monitor, the product score must be at least 50%. Anything lower will not be able to officially bear the HDSS® logo. The major specifics of HDSS® require that:

A) The audio monitor be of wide dynamic range with the ability to respond to very low level signals with a great degree of linearity. Maximum level is relative to application.

B) The audio monitor maintain that range at all vertical and horizontal angles within the room so as to include room reflections at the ear. Intelligibility must not suffer.

C) The audio range must be high pass limited to include sub 100 Hz signals while having a moderate slope below that low cutoff frequency. Subwoofer is optional for HDSS®

TBI is currently establishing the weighting values while ongoing research defines the relative effect of some less offensive negative issues required in various applications.

Originally Posted by adwilk on the Audioholics.com forum

“Alright, I’ll bite…..

I haven’t heard the sub in question… let me clarify that.

I have “extensive” experience now with the DAD-1 and TBI’s Monitor sporting the ETL technology.

The Dialog Augmentation Device (DAD) comes as advertised. The product wasn’t developed for its marketing venture, but it really does work. I hooked it up to my parents HTIB and my brother’s entry level theater and the dialog from the respective center channels improved considerably. The largest consumer group doesnt care about measurements and whatnot and just demands the most performance for their money and the DAD can provide that. I’ll endorse the upgrade…

Now, on to the monitors…

After having heard the DAD, I was very excited to try the monitors. I was disappointed with the sound out of the box. TBI’s service was great and sent me an updated driver that should have improved the sound.

Those monitors aren’t gonna pull rank in any listening room of mine, but…. The in room response tells me that the T/S specs can be thrown out when ETL is applied. The driver had significant output below 60hz and using dayton’s woofer tester would lead one to believe a drastic roll off would occur around 120. I honestly don’t care for the sound of the monitor, but I think the driver’s performance was greatly approved by the application of ETL.”

Majestic Diamond™ II

“These are perfect monitors and are small enough to get high-end audio from your computer.”

“I would have given them 5.5 stars, which is remarkable for loudspeakers under $1K/pr. We have a winner!”

Strengths:
“Natural sound and a joy to listen to.”

Weaknesses:
“None when considered as a true near-field monitor, which is what they are.”

Click here (AudioReview.com™) and also view BioDaddy’s comment

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